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A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 xtrm0 3545
#2 eleemosynator 2275
#3 wyan 1930
#4 urmastoobal 1890
#5 manbolq 1575
Recent Solves
Adrien's Signs sampaixd
Base64 fporto
Hex fporto
RSA Starter 4 Urkon
XOR Starter ZiadEslam
Recent Solutions
Extended GCD Psi505 0
Quadratic Residues Psi505 0
d-phi-enc (HackTM CTF) ConnorM 0
RSA Starter 2 rughtr 0
1337crypt (DownUnderCTF) ConnorM 0

Level Up

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